June 28, 2014

The End of Lunar Studies

Scan of small piece of "Mappa Selenographica" by Beer and Mädler

In 1837 a map and book appeared that were so masterful that it was widely assumed that the study of the Moon was then completed. Wilhelm Beer and Johann Heinrich Mädler were the authors, but Beer was the banker who provided the observatory and 3.75" refractor, and Mädler was the observer, artist and scientist who drew the map, Mappa Selenographica, and wrote the classic book, Der Mond. Mädler spent 600 nights observing the Moon. He determined hundreds of crater positions and diameters, measured heights of 800 peaks, and gave more than 100 new names. Strangely, Der Mond was never translated into English, but the principal conclusions have endured: the Moon has no atmosphere, water nor changes. Mädler characterized crater rays and rilles and established a classification of craters. He recognized that lunar craters were unlike any on Earth, and his conclusion still stands: "The Moon is no copy of the Earth"

Chuck Wood
This is a replay of a classic LPOD from the first weeks of its existence in 2004. Weren't images small back then!

Technical Details:
This scanned small portion of the Beer & Mädler map doesn't do justice to its careful detail. The craters shown are Alpetragius, Arzachel and Thebit with the Straight Wall labeled with a barely legible, long-tailed Greek letter beta.